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Effects of PNPG on cell growth cycle, motility machinery and quorum sensing in Serratia marcescens

Jun-Rong Wei1, Yu-Tze Horng, Hsin-Chih Lai

  • 1School and Graduate Institute of Medical Technology, College of Medicine, National Taiwan University, Taipei, Taiwan, ROC.

Journal of Microbiology, Immunology, and Infection = Wei Mian Yu Gan Ran Za Zhi
|April 3, 2004
PubMed

Insights

p-Nitrophenylglycerol (PNPG) inhibits bacterial swarming and motility in Serratia marcescens. This compound affects flagellar gene expression and quorum sensing, impacting bacterial physiology.

Area of Science:

  • Microbiology
  • Bacterial Physiology

Background:

  • Swarming motility is a complex behavior in enterobacteria.
  • The mechanism by which p-Nitrophenylglycerol (PNPG) inhibits swarming in Proteus mirabilis is not fully understood.

Purpose of the Study:

  • To investigate the effect of PNPG on swarming and motility in Serratia marcescens.
  • To elucidate the molecular mechanisms underlying PNPG's inhibitory action on bacterial swarming.

Main Methods:

  • Assessing the impact of PNPG on bacterial growth rates.
  • Analyzing the expression of key genes involved in flagellar motility (flhDCSm, hagSm) and nuclease activity (nucASm) in S. marcescens.
  • Quantifying quorum-sensing signal molecule production in response to PNPG.

Main Results:

  • PNPG was found to inhibit swarming and motility in Serratia marcescens.
  • PNPG caused a delay in the expression of flagellar genes and nuclease genes, correlating with reduced growth rates.
  • PNPG also delayed quorum-sensing signal molecule production and reduced their overall levels.

Conclusions:

  • PNPG exhibits a pleiotropic effect on Serratia marcescens physiology, impacting multiple aspects related to swarming.
  • The precise molecular mechanism of PNPG's inhibitory action on swarming requires further investigation.

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